Conventionally, the data of the information items indicating the status of the vehicle (including the in-vehicle equipment of the vehicle, hereinafter collectively referred to as “a vehicle”) have been monitored in a vehicle. Further, when a malfunction is detected in the vehicle, the data of the information items indicating the status of the vehicle are stored into a non-volatile storage medium or the like. Then, the data of the information items stored in the non-volatile storage medium or the like are used for the investigation of the cause of the malfunction. Such a process of investigating the cause of the malfunction may be called a diagnosis. It should be noted that a controlling device in the vehicle may be configure to store the data of the information items for the diagnosis while performing other vehicle control processes.
For example, Patent Document 1 discloses a vehicle information terminal apparatus capable of storing information items into a storage device for the diagnosis. The vehicle information terminal apparatus includes one or more vehicle electronic control devices, sensors, storage devices, and internal memories. The electronic control device includes a vehicle control program and a diagnosis program for diagnosing the status of the vehicle. The sensors acquire the data of status information items indicating the status of the vehicle (herein “vehicle information” in this paragraph). The vehicle information acquired from the vehicle electronic control device and sensors and a result of the diagnosis obtained by executing the diagnosis program are sequentially stored into the internal memory. Then, in a case where a malfunction is detected in the vehicle based on the result of the diagnosis, the vehicle information stored within a specific range in the internal memory are copied into the storage device, the specific range being determined as a predetermined time period until the malfunction is detected.                Patent Document 1: Japanese Patent Application Publication No. 2005-43138        